Imaging lens system and image capturing device

ABSTRACT

An imaging lens system includes six non-cemented lens elements with refractive power, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element has positive refractive power. The second lens element has refractive power. The third lens element has positive refractive power. The fourth lens element has refractive power. The fifth lens element has refractive power, wherein both of the surfaces thereof are aspheric. The sixth lens element with refractive power has a concave image-side surface in a paraxial region thereof, wherein the image-side surface has at least one convex shape in an off-axis region thereof, and both of the surfaces thereof are aspheric. The imaging lens system has a total of six lens elements with refractive power.

RELATED APPLICATIONS

This application claims priority to Taiwan Application Serial Number102119136, filed May 30, 2013, which is incorporated by reference hereinin its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to an imaging lens system. Moreparticularly, the present disclosure relates to a compact imaging lenssystem applicable to electronic products.

2. Description of Related Art

In recent years, with the popularity of mobile products having camerafunctionalities, the demand of miniaturized optical systems has beenincreasing. The sensor of a conventional optical system is typically aCCD (Charge-Coupled Device) or a CMOS (ComplementaryMetal-Oxide-Semiconductor) sensor. As the advanced semiconductormanufacturing technologies have allowed the pixel size of sensors to bereduced and compact optical systems have gradually evolved toward thefield of higher megapixels, there is an increasing demand for compactoptical systems featuring better image quality.

A conventional optical system employed in a portable electronic productmainly adopts a four-element lens structure or a five-element lensstructure. Due to the popularity of mobile products with high-endspecifications, such as smart phones and tablet personal computers, therequirements for high resolution and image quality of present compactoptical systems increase significantly. However, the conventionaloptical systems cannot satisfy these requirements of the compact opticalsystems.

Other conventional compact optical systems with six-element lensstructure enhance image quality and resolution. However, the axialdistance between the first lens element and the second lens elementtends to cause problems in assembling. Moreover, most of the refractivepowers center on the object-side of the optical systems which mightresult in worse image quality due to high sensitivity of tolerance.

SUMMARY

According to one aspect of the present disclosure, an imaging lenssystem includes six non-cemented lens elements with refractive power, inorder from an object side to an image side, a first lens element, asecond lens element, a third lens element, a fourth lens element, afifth lens element and a sixth lens element. The first lens element haspositive refractive power. The second lens element has refractive power.The third lens element has positive refractive power. The fourth lenselement has refractive power. The fifth lens element has refractivepower, wherein both of an object-side surface and an image-side surfaceof the fifth lens element are aspheric. The sixth lens element withrefractive power has a concave image-side surface in a paraxial regionthereof, wherein the image-side surface of the sixth lens element has atleast one convex shape in an off-axis region thereof, and both of anobject-side surface and the image-side surface of the sixth lens elementare aspheric. The imaging lens system has a total of six lens elementswith refractive power. When a focal length of the first lens element isf1, a focal length of the third lens element is f3, a curvature radiusof the object-side surface of the fifth lens element is R9, a curvatureradius of the image-side surface of the fifth lens element is R10, acentral thickness of the first lens element is CT1, and an axialdistance between the first lens element and the second lens element isT12, the following relationships are satisfied:

0<f3/f1<1.1;

|R9/R10|<3.0; and

0.90<T12/CT1<3.0.

According to another aspect of the present disclosure, an imaging lenssystem includes six non-cemented lens elements with refractive power, inorder from an object side to an image side, a first lens element, asecond lens element, a third lens element, a fourth lens element, afifth lens element and a sixth lens element. The first lens element haspositive refractive power. The second lens element has negativerefractive power. The third lens element has positive refractive power.The fourth lens element with refractive power has a concave object-sidesurface and a convex image-side surface. The fifth lens element withrefractive power has a convex object-side surface, wherein both of anobject-side surface and an image-side surface of the fifth lens elementare aspheric. The sixth lens element with refractive power has a concaveimage-side surface in a paraxial region thereof, wherein the image-sidesurface of the sixth lens element has at least one convex shape in anoff-axis region thereof, and both of an object-side surface and themage-side surface of the sixth lens element are aspheric. The imaginglens system has a total of six lens elements with refractive power. Whena focal length of the first lens element is f1, a focal length of thethird lens element is f3, a curvature radius of the object-side surfaceof the fifth lens element is R9, a curvature radius of the image-sidesurface of the fifth lens element is R10, a curvature radius of theobject-side surface of the sixth lens element is R11, and a curvatureradius of the image-side surface of the sixth lens element is R12, thefollowing relationships are satisfied:

0<f3/f1<1.1;

-   |R9/R10|<3.0; and

−1.0<(R11+R12)/(R11−R12)<2.75.

According to still another aspect of the present disclosure, an imagecapturing device includes the imaging lens system according to saidaspect and an image sensor. The image sensor is located on an mage planeside of said imaging lens system.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure can be more fully understood by reading thefollowing detailed description of the embodiment, with reference made tothe accompanying drawings as follows:

FIG. 1 is a schematic view of an imaging lens system according to the1st embodiment of the present disclosure;

FIG. 2 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 1stembodiment;

FIG. 3 is a schematic view of an imaging lens system according to the2nd embodiment of the present disclosure;

FIG. 4 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 2ndembodiment;

FIG. 5 is a schematic view of an imaging lens system according to the3rd embodiment of the present disclosure;

FIG. 6 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 3rdembodiment;

FIG. 7 is a schematic view of an imaging lens system according to the4th embodiment of the present disclosure;

FIG. 8 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 4thembodiment;

FIG. 9 is a schematic view of an imaging lens system according to the5th embodiment of the present disclosure;

FIG. 10 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 5thembodiment;

FIG. 11 is a schematic view of an imaging lens system according to the6th embodiment of the present disclosure;

FIG. 12 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 6thembodiment;

FIG. 13 is a schematic view of an imaging lens system according to the7th embodiment of the present disclosure;

FIG. 14 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 7thembodiment;

FIG. 15 is a schematic view of an imaging lens system according to the8th embodiment of the present disclosure; and

FIG. 16 shows spherical aberration curves, astigmatic field curves and adistortion curve of the imaging lens system according to the 8thembodiment.

DETAILED DESCRIPTION

An imaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, a firstlens element, a second lens element, a third lens element, a fourth lenselement, a fifth lens element and a sixth lens element. The imaging lenssystem has a total of six lens elements with refractive power andfurther includes an image sensor located on an image plane.

The first lens element, the second lens element, the third lens element,the fourth lens element, the fifth lens element, and the sixth lenselement are six non-cemented lens elements with refractive power. Thatis, any two lens elements adjacent to each other are not cemented, andthere is an air space between the two lens elements. Moreover, themanufacturing process of the cemented lenses is more complex than thenon-cemented lenses. In particular, a second surface of one lens and afirst surface of the following lens need to have accurate curvature toensure these two lens elements will be highly cemented. However, duringthe cementing process, those two lens elements might not be highlycemented due to displacement and it is thereby not favorable for theimage quality of the imaging lens system. Therefore, the imaging lenssystem of the present disclosure provides six non-cemented lens elementsfor improving the problem generated by the cemented lens elements.

The imaging lens system can further include a stop, such as an aperturestop, and the image sensor. The stop can be disposed between an imagedobject and the second lens element, and the image sensor can be locatedon the image plane, wherein the image sensor has a resolution of atleast 10 megapixeis so as to improve image quality.

The first lens element with positive refractive power can have a convexobject-side surface. Therefore, it is favorable for properly adjustingthe positive refractive power of the first lens element so as to reducethe total track length of the imaging lens system.

The second lens element can have negative refractive power, a convexobject-side surface and a concave image-side surface, so that theaberration generated by the first lens element can be corrected.

The third lens element with positive refractive power can have a conveximage-side surface. Therefore, the positive refractive power of thefirst lens element can be balanced for avoiding the excessive sphericalaberration and reducing the photosensitivity of the imaging lens system.

The fourth lens element can have negative refractive power, a concaveobject-side surface and a convex image-side surface. Therefore, thePetzval sum and the astigmatism of the imaging lens system can becorrected effectively so as to correct the image curvature.

The fifth lens element can have positive refractive power, a convexobject-side surface in a paraxial region thereof, wherein theobject-side surface of the fifth lens element has at least one concaveshape in an off-axis region thereof. Therefore, the spherical aberrationcan be effectively corrected, and the coma aberration together with theastigmatism from the off-axis field can also be corrected.

The sixth lens element can have negative refractive power, and has aconcave image-side surface in a paraxial region thereof, wherein theimage-side surface of the sixth lens element has at least one convexshape in an off-axis region thereof. Therefore, the principal point ofthe imaging lens system can be positioned away from the image plane, andthe back focal length thereof can be reduced so as to keep the imaginglens system compact. Furthermore, the incident angle of the off-axis onthe image plane can be reduced in order to correct the aberration of theoff-axis.

When a focal length of the first lens element is f1, and a focal lengthof the third lens element is f3, the following relationship issatisfied: 0<f3/f1<1.1. Therefore, it is favorable for avoidingoverloading the refractive power on the lens elements which are close tothe object-side of the imaging lens system so as to reduce thesensitivity of tolerance. Preferably, the following relationship issatisfied: 0.20<f3/f1<0.85.

When a curvature radius of the object-side surface of the fifth lenselement is R9, and a curvature radius of the image-side surface of thefifth lens element is R10, the following relationship is satisfied:|R9/R10|<3.0. Therefore, it is favorable for effectively correct theastigmatism and the spherical aberration. Preferably, the followingrelationship is satisfied: |R9/R10|<1.0.

When a central thickness of the first lens element is CT1, and an axialdistance between the first lens element and the second lens element isT12, the following relationship is satisfied: 0.90<T12/CT1<3.0. A properaxial distance between the first lens element and the second lenselement is favorable for avoiding tiny axial distance between the firstand the second lens elements during assembling.

When a central thickness of the second lens element is CT2, and theaxial distance between the first lens element and the second lenselement is T12, the following relationship is satisfied:1.20<T12/CT2<3.0. It is favorable for avoiding tiny axial distancebetween lens elements during assembling so as to maintain the imaginglens system a corn pact size.

When an Abbe number of the second lens element is V2, an Abbe number ofthe fourth lens element is V4, and an Abbe number of the sixth lenselement is V6, the following relationship is satisfied:0.60<(V2+V4)/V6<1.10. Therefore, the chromatic aberration of the imaginglens system can be corrected.

When a curvature radius of the object-side surface of the sixth lenselement is R11, and a curvature radius of the image-side surface of thesixth lens element is R12, the following relationship is satisfied:−1.0<(R11+R12)/(R11−R12)<2.75. Therefore, the principal point can bepositioned away from the image plane which is favorable for reducing thetotal track length so as to maintain a compact size for the imaging lenssystem. Preferably, −0.50<(R11+R12)/(R11−R12)<2.50.

When an axial distance between the fifth lens element and the sixth lenselement is T56, and a central thickness of the sixth lens element isCT6, the following relationship is satisfied: 0.8<T56/CT6<2.5.Therefore, a proper axial distance between the fifth and the sixth lenselements and a proper thickness of the sixth lens element are favorablefor assembling and manufacturing.

When a focal length of the imaging lens system is f, and half of amaximal field of view of the imaging lens system is HFOV, the followingrelationship is satisfied: 5.5 mm<f×tan(HFOV)<10 mm. Therefore, it isfavorable for capturing adequate image scene and improving imagequality.

According to the imaging lens system of the present disclosure, the lenselements can be made of plastic or glass material. When the lenselements are made of glass material, the distribution of the refractivepower of the imaging lens system can be more flexible to design. Whenthe lens elements are made of plastic material, the manufacturing costthereof can be reduced. Furthermore, surfaces of each lens element canbe arranged to be aspheric, because the aspheric surface of the lenselement is easy to form a shape other than spherical surface so as tohave more controllable variables for eliminating the aberration thereof,and to further decrease the required number of the lens elements. Thus,the total track length of the imaging lens system can be effectivelyreduced.

According to the imaging lens system of the present disclosure, anaperture stop can be configured as a front stop or a middle stop. Afront stop disposed between an imaged object and the first lens elementcan provide a longer distance between an exit pupil of the system and animage plane and which improves the image-sensing efficiency of the imagesensor. A middle stop disposed between the first lens element and theimage plane is favorable for enlarging the field of view of the systemand thereby provides a wider field of view for the same.

According to the imaging lens system of the present disclosure, theimaging lens system can include at least one stop, such as an aperturestop, a glare stop or a field stop. Said glare stop or said field stopis for eliminating the stray light and thereby improving the imageresolution thereof.

According to the imaging lens system of the present disclosure, when thelens element has a convex surface, it indicates that the surface isconvex in the paraxial region thereof; and when the lens element has aconcave surface, it indicates that the surface is concave in theparaxial region thereof. Particularly, the paraxial region thereofrefers to the region of the surface where light rays travel close to anoptical axis and an off-axis region thereof refers to the region of thesurface where light rays travel away from the optical axis.

According to the imaging lens system of the present disclosure, theimaging lens system is featured with good correction ability and highimage quality, and can be applied to 3D (three-dimensional) imagecapturing applications, in products such as digital cameras, mobiledevices and tablets.

According to the present disclosure, an image capturing device isprovided. The image capturing device includes the imaging lens systemaccording to the aforementioned imaging lens system of the presentdisclosure, and an image sensor located on an image plane side of saidimaging lens system.

According to the above description of the present disclosure, thefollowing 1st-8th specific embodiments are provided for furtherexplanation.

1st Embodiment

FIG. 1 is a schematic view of an imaging lens system according to the1st embodiment of the present disclosure. FIG. 2 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 1st embodiment. In FIG. 1, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 100, a first lens element 110, a second lens element 120,a third lens element 130, a fourth lens element 140, a fifth lenselement 150, a sixth lens element 160, an IR-cut filter 180, an imageplane 170 and an image sensor 190, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 110 with positive refractive power has a convexobject-side surface 111 and a concave image-side surface 112. The firstlens element 110 is made of plastic material, and has the object-sidesurface 111 and the image-side surface 112 being both aspheric.

The second lens element 120 with negative refractive power has a convexobject-side surface 121 and a concave image-side surface 122. The secondlens element 120 is made of plastic material, and has the object-sidesurface 121 and the image-side surface 122 being both aspheric.

The third lens element 130 with positive refractive power has a convexobject-side surface 131 and a convex image-side surface 132. The thirdlens element 130 is made of plastic material, and has the object-sidesurface 131 and the image-side surface 132 being both aspheric.

The fourth lens element 140 with negative refractive power has a concaveobject-side surface 141 and a convex image-side surface 142. The fourthlens element 140 is made of plastic material, and has the object-sidesurface 141 and the image-side surface 142 being both aspheric.

The fifth lens element 150 with positive refractive power has a convexobject-side surface 151 in a paraxial region thereof and a concaveimage-side surface 152, wherein the object-side surface 151 of the fifthlens element 150 has a concave shape in an off-axis region thereof. Thefifth lens element 150 is made of plastic material, and has theobject-side surface 151 and the image-side surface 152 being bothaspheric.

The sixth lens element 160 with negative refractive power has a convexobject-side surface 161 and a concave image-side surface 162 in aparaxial region thereof, wherein the image-side surface 162 of the sixthlens element 160 has a convex shape in an off-axis region thereof. Thesixth lens element 160 is made of plastic material, and has theobject-side surface 161 and the image-side surface 162 being bothaspheric.

The IR-cut filter 180 is made of glass material and located between thesixth lens element 160 and the image plane 170, and will not affect thefocal length of the imaging lens system.

The equation of the aspheric surface profiles of the aforementioned lenselements of the 1st embodiment is expressed as follows:

${X(Y)} = {{\left( {Y^{2}\text{/}R} \right)\text{/}\left( {1 + {{sqrt}\left( {1 - {\left( {1 + k} \right) \times \left( {Y\text{/}R} \right)^{2}}} \right)}} \right)} + {\sum\limits_{t}\; {({Ai}) \times \left( Y^{i} \right)}}}$

wherein,

X is the relative distance between a point on the aspheric surfacespaced at a distance Y from the optical axis and the tangential plane atthe aspheric surface vertex on the optical axis;

Y is the distance from the point on the curve f the aspheric surface tothe optical axis;

R is the curvature radius;

k is the conic coefficient; and

Ai is the i-th aspheric coefficient.

In the imaging lens system according to the 1st embodiment, when a focallength of the imaging lens system is f, an f-number of the imaging lenssystem is Fno, and half of a maximal field of view of the imaging lenssystem is HFOV, these parameters have the following values; f=7.46 mm;Fno=2.40; and HFOV=41.8 degrees.

In the imaging lens system according, to the 1st embodiment, when anAbbe number of the second lens element 120 is V2, an Abbe number of thefourth lens element 140 is V4, and an Abbe number of the sixth lenselement 160 is V6, the following relationship is satisfied:(V2+V4)/V6=0.83.

In the imaging lens system according to the 1st embodiment, when anaxial distance between the first lens element 110 and the second lenselement 120 is T12, a central thickness of the first lens element 110 isCT1, and a central thickness of the second lens element 120 is CT2, thefollowing relationships are satisfied: T12/CT1=1.31; and T12/CT2=1.67.

In the imaging lens system according to the 1st embodiment, when anaxial distance between the fifth lens element 150 and the sixth lenselement 160 is T56, and a central thickness of the sixth lens element160 is CT6, the following relationship is satisfied: T56/CT6=1.13.

In the imaging lens system according to the 1st embodiment, when acurvature radius of the object-side surface 151 of the fifth lenselement 150 is R9, and a curvature radius of the image-side surface 152of the fifth lens element 150 is R10, the following relationship issatisfied: |R9/R10|=0.09.

In the imaging lens system according to the 1st embodiment, when acurvature radius of the object-side surface 161 of the sixth lenselement 160 is R11, and a curvature radius of the image-side surface 162of the sixth lens element 160 is R12, the following relationship issatisfied: (R11+R12)/(R11−R12)=220.

In the imaging lens system according to the 1st embodiment, when a focallength of the first lens element 110 is f1, and a focal length of thethird lens element 130 is f3, the following relationship is satisfied:f3/f1=0.58.

In the imaging lens system according to the 1st embodiment, when thefocal length of the imaging lens system is f, and half of the maximalfield of view of the imaging lens system is HFOV, the followingrelationship is satisfied: f×tan(HFOV)=6.67 mm.

The detailed optical data of the 1st embodiment are shown in Table 1 andthe aspheric surface data are shown in Table 2 below.

TABLE 1 1st Embodiment f = 7.46 mm, Fno = 2.40, HFOV = 41.8 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # Length 0Object Plano Infinity 1 Ape. Stop Plano −0.224 2 Lens 1 4.942 ASP 0.740Plastic 1.544 55.9 12.54 3 16.983 ASP 0.969 4 Lens 2 7.400 ASP 0.580Plastic 1.640 23.3 −19.68 5 4.519 ASP 0.402 6 Lens 3 15.632 ASP 1.569Plastic 1.544 55.9 7.28 7 −5.115 ASP 0.900 8 Lens 4 −1.439 ASP 0.737Plastic 1.640 23.3 −8.16 9 −2.383 ASP 0.080 10 Lens 5 3.242 ASP 1.354Plastic 1.544 55.9 6.44 11 36.649 ASP 1.017 12 Lens 6 7.597 ASP 0.901Plastic 1.544 55.9 −8.95 13 2.843 ASP 1.000 14 IR-cut Plano 0.300 Glass1.517 64.2 — filter 15 Plano 0.623 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 2 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −9.7110E−01−1.0000E+00 −2.0634E+01 −1.1173E+00 −1.0000E+00 6.3510E−01 A4 =−1.1527E−03 −5.8017E−03 −1.0297E−02 −1.5169E−02 −7.9494E−03 −9.0250E−03A6 = −4.3736E−04 −3.4409E−04 2.4551E−04 2.4859E−03 1.5997E−03 2.9227E−03A8 = −1.4543E−05 −3.5399E−04 −4.0418E−04 −5.4280E−04 −5.3404E−04−1.1486E−03 A10 = −4.7264E−05 8.4473E−05 6.2887E−05 6.9150E−051.7480E−04 2.9322E−04 A12 = −1.8098E−05 −3.4768E−06 −3.2370E−06−3.7268E−05 −3.7305E−05 A14 = 1.9867E−07 −2.0476E−08 4.0311E−062.2022E−06 A16 = −1.6968E−07 −4.5518E−08 Surface # 8 9 10 11 12 13 k =−2.0827E+00 −2.3134E+00 −5.6119E+00 1.4381E+01 −2.8376E+01 −5.4380E+00A4 = 1.1923E−02 6.7194E−03 −1.5423E−03 2.0664E−03 −1.7533E−02−7.1835E−03 A6 = −6.2607E−03 −3.5571E−03 5.1460E−04 3.7121E−042.6061E−03 8.0576E−04 A8 = 1.6309E−03 8.7114E−04 −6.9384E−05 −8.0423E−05−2.7989E−04 −7.1096E−05 A10 = −1.8418E−04 −1.1076E−04 3.8462E−064.8477E−06 1.8614E−05 3.9886E−06 A12 = 8.8328E−06 7.9452E−06 −1.2632E−07−1.2611E−07 −6.9640E−07 −1.2999E−07 A14 = −3.2751E−08 −2.8877E−072.3633E−09 1.2262E−09 1.3549E−08 2.2237E−09 A16 = −8.0881E−09 3.8230E−09−1.6062E−11 −1.0737E−10 −1.5400E−11

In Table 1, the curvature radius, the thickness and the focal Length areshown in millimeters (mm). Surface numbers 0-16 represent the surfacessequentially arranged from the object-side to the image-side along theoptical axis. In Table 2, k represents the conic coefficient of theequation of the aspheric surface profiles. A1-A16 represent the asphericcoefficients ranging from the 1st order to the 16th order. Thisinformation related to Table 1 and Table 2 applies also to the Tablesfor the remaining embodiments, and so an explanation in this regard willnot be provided again.

2nd Embodiment

FIG. 3 is a schematic view of an imaging lens system according to the2nd embodiment of the present disclosure. FIG. 4 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 2nd embodiment. In FIG. 3, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 200, a first lens element 210, a second lens element 220,a third lens element 230, a fourth lens element 240, a fifth lenselement 250, a sixth lens element 260, an IR-cut filter 280, an imageplane 270 and an image sensor 290, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 210 with positive refractive power has a convexobject-side surface 211 and a concave image-side surface 212. The firstlens element 210 is made of plastic material, and has the object-sidesurface 211 and the image-side surface 212 being both aspheric.

The second lens element 220 with negative refractive power has a convexobject-side surface 221 and a concave image-side surface 222. The secondlens element 220 is made of plastic material, and has the object-sidesurface 221 and the image-side surface 222 being both aspheric.

The third lens element 230 with positive refractive power has a convexobject-side surface 231 and a convex image-side surface 232. The thirdlens element 230 is made of plastic material, and has the object-sidesurface 231 and the image-side surface 232 being both aspheric.

The fourth lens element 240 with negative refractive power has a concaveobject-side surface 241 and a convex image-side surface 242. The fourthlens element 240 is made of plastic material, and has the object-sidesurface 241 and the image-side surface 242 being both aspheric.

The fifth lens element 250 with positive refractive power has a convexobject-side surface 251 in a paraxial region thereof and a concaveimage-side surface 252, wherein the object-side surface 251 of the fifthlens element 250 has a concave shape in an off-axis region thereof. Thefifth lens element 250 is made of plastic material, and has theobject-side surface 251 and the image-side surface 252 being bothaspheric.

The sixth lens element 260 with negative refractive power has a concaveobject-side surface 261 and a concave image-side surface 262 in aparaxial region thereof, wherein the image-side surface 262 of the sixthlens element 260 has a convex shape in an off-axis region thereof. Thesixth lens element 260 is made of plastic material, and has theobject-side surface 261 and the image-side surface 262 being bothaspheric.

The IR-cut filter 280 is made of glass material and located between thesixth lens element 260 and the image plane 270, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 2nd embodiment are shown in Table 3 andthe aspheric surface data are shown in Table 4 below.

TABLE 3 2nd Embodiment f = 9.02 mm, Fno = 2.40, HFOV = 41.7 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Ape. Stop Plano −0.160 2 Lens 1 6.297 ASP1.529 Plastic 1.535 55.7 12.84 3 69.061 ASP 0.857 4 Lens 2 11.905 ASP0.709 Plastic 1.640 23.3 −19.88 5 6.006 ASP 0.343 6 Lens 3 18.735 ASP1.866 Plastic 1.535 55.7 8.62 7 −5.903 ASP 0.383 8 Lens 4 −1.693 ASP0.861 Plastic 1.640 23.3 −11.27 9 −2.652 ASP 0.156 10 Lens 5 3.407 ASP1.578 Plastic 1.535 55.7 6.46 11 200.000 ASP 1.039 12 Lens 6 −7.146 ASP0.600 Plastic 1.544 55.9 −6.89 13 8.120 ASP 1.000 14 IR-cut Plano 0.300Glass 1.517 64.2 — filter 15 Plano 1.785 16 Image Plano — Note:Reference wavelength is 587.6 nm (d-line).

TABLE 4 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −1.1854E+00−1.0000E+00 −6.4639E+01 −1.7335E+00 −1.0000E+00 1.0872E+00 A4 =−7.7849E−04 −5.7731E−03 −8.8814E−03 −1.1694E−02 −8.2526E−03 −7.3654E−03A6 = −1.3914E−04 −1.8117E−04 −2.0522E−04 1.4262E−03 4.4887E−041.0615E−03 A8 = −8.4535E−06 −1.2525E−04 −2.3901E−04 −2.6754E−04−1.4071E−05 −1.3013E−04 A10 = −7.5571E−06 1.6625E−05 1.8917E−052.5394E−05 −3.3177E−06 7.5081E−06 A12 = −1.7312E−06 −1.7179E−06−1.4741E−06 6.2565E−07 1.7665E−10 A14 = −1.3046E−08 3.7050E−08−2.6559E−08 −7.5100E−09 Surface # 8 9 10 11 12 13 k = −2.8785E+00−3.2186E+00 −5.8168E+00 −9.0000E+01 −1.6035E−01 −1.8602E+00 A4 =1.6642E−03 4.5159E−04 −2.6193E−03 −1.2835E−03 −2.3471E−03 −5.3208E−03 A6= 2.2490E−04 −5.5856E−06 3.7463E−04 3.0192E−04 −1.0833E−04 1.8341E−04 A8= −9.0355E−06 5.4486E−06 −4.7510E−05 −1.8506E−05 3.7673E−05 3.5329E−06A10 = 1.1187E−06 8.8240E−09 2.7059E−06 −1.9774E−06 −2.1556E−06−5.3025E−07 A12 = −1.5240E−07 1.6782E−08 −2.0676E−07 2.1039E−075.7706E−08 1.6657E−08 A14 = 2.3510E−09 −1.4565E−10 9.4289E−09−6.5658E−09 −7.8199E−10 −2.1701E−10 A16 = −1.4259E−10 6.8254E−114.3750E−12 1.0074E−12

In the imaging lens system according to the 2nd embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 2nd embodiment. Moreover, these parameters can be calculated fromTable 3 and Table 4 as the following values and satisfy the followingrelationships:

2nd Embodiment f [mm] 9.02 T56/CT6 1.73 Fno 2.40 |R9/R10| 0.02 HFOV[deg.] 41.7 (R11 + R12)/(R11 − R12) −0.06 (V2 + V4)/V6 0.83 f3/f1 0.67T12/CT1 0.56 f × tan(HFOV) [mm] 8.04 T12/CT2 1.21

3rd Embodiment

FIG. 5 is a schematic view of an imaging lens system according to the3rd embodiment of the present disclosure. FIG. 6 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 3rd embodiment. In FIG. 5, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 300, a first lens element 310, a second lens element 320,a third lens element 330, a fourth lens element 340, a fifth lenselement 350, a sixth lens element 360, an IR-cut filter 380, an imageplane 370 and an image sensor 390, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 310 with positive refractive power has a convexobject-side surface 311 and a concave image-side surface 312. The firstlens element 310 is made of plastic material, and has the object-sidesurface 311 and the image-side surface 312 being both aspheric.

The second lens element 320 with negative refractive power has a convexobject-side surface 321 and a concave image-side surface 322. The secondlens element 320 is made of plastic material, and has the object-sidesurface 321 and the image-side surface 322 being both aspheric.

The third lens element 330 with positive refractive power has a convexobject-side surface 331 and a convex image-side surface 332. The thirdlens element 330 is made of plastic material, and has the object-sidesurface 331 and the image-side surface 332 being both aspheric.

The fourth lens element 340 with negative refractive power has a concaveobject-side surface 341 and a convex image-side surface 342. The fourthlens element 340 is made of plastic material, and has the object-sidesurface 341 and the image-side surface 342 being both aspheric.

The fifth lens element 350 with positive refractive power has a convexobject-side surface 351 in a paraxial region thereof and a concaveimage-side surface 352, wherein the object-side surface 351 of the fifthlens element 350 has a concave shape in an off-axis region thereof. Thefifth lens element 350 is made of plastic material, and has theobject-side surface 351 and the image-side surface 352 being bothaspheric.

The sixth lens element 360 with negative refractive power has a concaveobject-side surface 361 and a concave image-side surface 362 in aparaxial region thereof, wherein the image-side surface 362 of the sixthlens element 360 has a convex shape in an off-axis region thereof. Thesixth lens element 360 is made of plastic material, and has theobject-side surface 361 and the image-side surface 362 being bothaspheric.

The IR-cut filter 380 is made of glass material and located between thesixth lens element 360 and the image plane 370, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 3rd embodiment are shown in Table 5 andthe aspheric surface data are shown in Table 6 below.

TABLE 5 3rd Embodiment f = 6.79 mm, Fno = 2.40, HFOV = 41.5 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Ape. Stop Plano −0.112 2 Lens 1 4.643 ASP0.881 Plastic 1.535 55.7 10.96 3 20.851 ASP 0.748 4 Lens 2 6.404 ASP0.500 Plastic 1.640 23.3 −16.20 5 3.838 ASP 0.306 6 Lens 3 9.136 ASP1.508 Plastic 1.535 55.7 6.68 7 −5.536 ASP 0.489 8 Lens 4 −1.289 ASP0.600 Plastic 1.640 23.3 −8.24 9 −2.017 ASP 0.102 10 Lens 5 2.773 ASP1.158 Plastic 1.535 55.7 5.82 11 21.523 ASP 1.401 12 Lens 6 −11.139 ASP0.700 Plastic 1.535 55.7 −6.67 13 5.371 ASP 0.600 14 IR-cut Plano 0.300Glass 1.517 64.2 — filter 15 Plano 0.626 16 Image Plano — Note:Reference wavelength is 587.6 nm (d-line).

TABLE 6 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −9.2497E−01−1.0000E+00 −2.1071E+01 −6.5962E−01 −1.0000E+00 1.1387E+00 A4 =−1.6473E−03 −1.0331E−02 −1.7107E−02 −2.6487E−02 −1.2410E−02 −1.5864E−02A6 = −1.0455E−03 −1.5968E−04 1.5329E−03 6.9089E−03 3.2098E−03 5.0794E−03A8 = 1.1566E−04 −1.1870E−03 −1.6335E−03 −2.1732E−03 −5.6750E−04−9.9010E−04 A10 = −1.1882E−04 3.4919E−04 3.0187E−04 3.8615E−04−1.0625E−05 1.0397E−04 A12 = −5.7891E−05 −4.2788E−05 −3.2496E−051.7175E−05 −2.0793E−06 A14 = 5.8454E−06 9.4448E−07 −1.4821E−06−2.2300E−07 Surface # 8 9 10 11 12 13 k = −2.0984E+00 −2.4205E+00−8.1586E+00 2.0000E+01 −2.7782E−01 −2.4506E+00 A4 = 9.4391E−03−1.7330E−03 8.5133E−03 7.2623E−03 −9.4415E−03 −1.2880E−02 A6 =4.8452E−04 3.8375E−03 −3.2981E−03 −2.3281E−03 −5.2099E−04 1.1092E−03 A8= −8.6643E−04 −1.6862E−03 6.8543E−04 3.6266E−04 2.5189E−04 −6.0443E−05A10 = 3.6359E−04 3.9457E−04 −9.5687E−05 −3.1853E−05 −2.5408E−052.0352E−06 A12 = −6.1184E−05 −4.8210E−05 8.2205E−06 1.3843E−061.2955E−06 −5.5291E−08 A14 = 4.5709E−06 2.9902E−06 −4.1168E−07−2.5506E−08 −3.4140E−08 1.3539E−09 A16 = −1.2921E−07 −7.4476E−088.9562E−09 1.1513E−10 3.6610E−10 −1.6975E−11

In the imaging lens system according to the 3rd embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 3rd embodiment. Moreover, these parameters can be calculated fromTable 5 and Table 6 as the following values and satisfy the followingrelationships:

3rd Embodiment f [mm] 6.79 T56/CT6 2.00 Fno 2.40 |R9/R10| 0.13 HFOV[deg.] 41.5 (R11 + R12)/(R11 − R12) 0.35 (V2 + V4)/V6 0.84 f3/f1 0.61T12/CT1 0.85 f × tan(HFOV) [mm] 6.01 T12/CT2 1.50

4th Embodiment

FIG. 7 is a schematic view of an imaging lens system according to the4th embodiment of the present disclosure. FIG. 8 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 4th embodiment. In FIG. 7, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 400, a first lens element 410, a second lens element 420,a third lens element 430, a fourth lens element 440, a fifth lenselement 450, a sixth lens element 460, an IR-cut filter 480, an imageplane 470 and an image sensor 490, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 410 with positive refractive power has a convexobject-side surface 411 and a concave image-side surface 412. The firstlens element 410 is made of plastic material, and has the object-sidesurface 411 and the image-side surface 412 being both aspheric.

The second lens element 420 with negative refractive power has a convexobject-side surface 421 and a concave image-side surface 422. The secondlens element 420 is made of plastic material, and has the object-sidesurface 421 and the image-side surface 422 being both aspheric.

The third lens element 430 with positive refractive power has a convexobject-side surface 431 and a convex image-side surface 432. The thirdlens element 430 is made of plastic material, and has the object-sidesurface 431 and the image-side surface 432 being both aspheric.

The fourth lens element 440 with negative refractive power has a concaveobject-side surface 441 and a convex image-side surface 442. The fourthlens element 440 is made of plastic material, and has the object-sidesurface 441 and the image-side surface 442 being both aspheric.

The fifth lens element 450 with positive refractive power has a convexobject-side surface 451 in a paraxial region thereof and a concaveimage-side surface 452, wherein the object-side surface 451 of the fifthlens element 450 has a concave shape in an off-axis region thereof. Thefifth lens element 450 is made of plastic material, and has theobject-side surface 451 and the image-side surface 452 being bothaspheric.

The sixth lens element 460 with negative refractive power has a convexobject-side surface 461 and a concave image-side surface 462 in aparaxial region thereof, wherein the image-side surface 462 of the sixthlens element 460 has a convex shape in an off-axis region thereof. Thesixth lens element 460 is made of plastic material, and has theobject-side surface 461 and the image-side surface 462 being bothaspheric.

The IR-cut filter 480 is made of glass material and located between thesixth lens element 460 and the image plane 470, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 4th embodiment are shown in Table 7 andthe aspheric surface data are shown in Table 8 below.

TABLE 7 4th Embodiment f = 6.74 mm, Fno = 2.40, HFOV = 41.7 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Ape. Stop Plano −0.218 2 Lens 1 4.275 ASP0.717 Plastic 1.544 55.9 11.27 3 13.278 ASP 0.862 4 Lens 2 6.180 ASP0.500 Plastic 1.640 23.3 −18.73 5 3.949 ASP 0.356 6 Lens 3 13.824 ASP1.474 Plastic 1.544 55.9 6.41 7 −4.492 ASP 0.700 8 Lens 4 −1.319 ASP0.732 Plastic 1.640 23.3 −7.10 9 −2.261 ASP 0.070 10 Lens 5 2.804 ASP1.256 Plastic 1.544 55.9 5.68 11 25.522 ASP 0.936 12 Lens 6 12.036 ASP0.804 Plastic 1.544 55.9 −7.72 13 3.041 ASP 0.800 14 IR-cut Plano 0.300Glass 1.517 64.2 — filter 15 Plano 0.628 16 Image Plano — Note:Reference wavelength is 587.6 nm (d-line).

TABLE 8 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −6.6279E−01−1.0000E+00 −1.7921E+01 −9.2320E−01 −1.0000E+00 6.6699E−01 A4 =−1.1493E−03 −7.4330E−03 −1.5027E−02 −2.3123E−02 −1.1456E−02 −1.1368E−02A6 = −5.7746E−04 −3.6398E−04 7.0124E−04 5.1548E−03 2.6614E−03 4.2576E−03A8 = 3.6107E−05 −7.5090E−04 −1.1459E−03 −1.5258E−03 −7.0715E−04−2.4729E−03 A10 = −1.2100E−04 2.2893E−04 2.3248E−04 2.5433E−042.6189E−04 9.8874E−04 A12 = −6.1412E−05 −1.7694E−05 −1.6685E−05−9.0827E−05 −1.9325E−04 A14 = −8.0633E−07 −6.3998E−08 1.5012E−051.7685E−05 A16 = −8.9067E−07 −6.0085E−07 Surface # 8 9 10 11 12 13 k =−2.0733E+00 −2.2812E+00 −5.1616E+00 1.5599E+01 −8.5979E+01 −4.8869E+00A4 = 2.3594E−02 1.0314E−02 −4.5346E−03 3.1730E−03 −1.5870E−02−9.9023E−03 A6 = −1.6796E−02 −6.7023E−03 1.4074E−03 −5.3507E−041.1222E−03 9.2950E−04 A8 = 6.0896E−03 2.1948E−03 −2.6263E−04 5.3723E−05−2.7328E−05 −6.2083E−05 A10 = −1.0808E−03 −3.9527E−04 2.7564E−05−4.7146E−06 4.4067E−07 3.0533E−06 A12 = 1.0366E−04 4.2285E−05−1.8564E−06 1.9719E−07 −4.4350E−08 −1.0510E−07 A14 = −5.0980E−06−2.4351E−06 6.7813E−08 −2.8951E−09 2.2333E−09 2.1313E−09 A16 =9.5952E−08 5.7123E−08 −9.7492E−10 −3.5133E−11 −1.8525E−11

In the imaging lens system according to the 4th embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 4th embodiment. Moreover, these parameters can be calculated fromTable 7 and Table 8 as the following values and satisfy the followingrelationships:

4th Embodiment f [mm] 6.74 T56/CT6 1.16 Fno 2.40 |R9/R10| 0.11 HFOV[deg.] 41.7 (R11 + R12)/(R11 − R12) 1.68 (V2 + V4)/V6 0.83 f3/f1 0.57T12/CT1 1.20 f × tan(HFOV) [mm] 6.01 T12/CT2 1.72

5th Embodiment

FIG. 9 is a schematic view of an imaging lens system according to the5th embodiment of the present disclosure. FIG. 10 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 5th embodiment. In FIG. 9, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 500, a first lens element 510, a second lens element 520,a third lens element 530, a fourth lens element 540, a fifth lenselement 550, a sixth lens element 560, an IR-cut filter 580, an imageplane 570 and an image sensor 590, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 510 with positive refractive power has a convexobject-side surface 511 and a concave image-side surface 512. The firstlens element 510 is made of plastic material, and has the object-sidesurface 511 and the image-side surface 512 being both aspheric.

The second lens element 520 with negative refractive power has a convexobject-side surface 521 and a concave image-side surface 522. The secondlens element 520 is made of plastic material, and has the object-sidesurface 521 and the image-side surface 522 being both aspheric.

The third lens element 530 with positive refractive power has a convexobject-side surface 531 and a convex image-side surface 532. The thirdlens element 530 is made of plastic material, and has the object-sidesurface 531 and the image-side surface 532 being both aspheric.

The fourth lens element 540 with negative refractive power has a concaveobject-side surface 541 and a convex image-side surface 542. The fourthlens element 540 is made of plastic material, and has the object-sidesurface 541 and the image-side surface 542 being both aspheric.

The fifth lens element 550 with positive refractive power has a convexobject-side surface 551 in a paraxial region thereof and a concaveimage-side surface 552, wherein the object-side surface 551 of the fifthlens element 550 has a concave shape in an off-axis region thereof. Thefifth lens element 550 is made of plastic material, and has theobject-side surface 551 and the image-side surface 552 being bothaspheric.

The sixth lens element 560 with negative refractive power has a convexobject-side surface 561 and a concave image-side surface 562 in aparaxial region thereof, wherein the image-side surface 562 of the sixthlens element 560 has a convex shape in an off-axis region thereof. Thesixth lens element 560 is made of plastic material, and has theobject-side surface 561 and the image-side surface 562 being bothaspheric.

The IR-cut filter 580 is made of glass material and located between thesixth lens element 560 and the image plane 570, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 5th embodiment are shown in Table 9 andthe aspheric surface data are shown in Table 10 below.

TABLE 9 5th Embodiment f = 6.82 mm, Fno = 2.40, HFOV = 41.5 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Ape. Stop Plano −0.207 2 Lens 1 4.503 ASP0.718 Plastic 1.544 55.9 11.86 3 14.065 ASP 0.766 4 Lens 2 6.089 ASP0.500 Plastic 1.640 23.3 −18.61 5 3.900 ASP 0.298 6 Lens 3 10.498 ASP1.415 Plastic 1.544 55.9 6.60 7 −5.201 ASP 0.640 8 Lens 4 −1.383 ASP0.660 Plastic 1.640 23.3 −7.91 9 −2.257 ASP 0.070 10 Lens 5 2.979 ASP1.217 Plastic 1.544 55.9 6.45 11 16.789 ASP 1.151 12 Lens 6 7.530 ASP0.800 Plastic 1.544 55.9 −8.43 13 2.745 ASP 1.000 14 IR-cut Plano 0.300Glass 1.517 64.2 — filter 15 Plano 0.445 16 Image Plano — Note:Reference wavelength is 587.6 nm (d-line).

TABLE 10 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −9.8303E−01−1.0000E+00 −1.6838E+01 −8.4978E−01 −1.0000E+00 1.0814E+00 A4 =−1.6192E−03 −8.4040E−03 −1.4032E−02 −2.2954E−02 −1.1006E−02 −1.1079E−02A6 = −5.5481E−04 −1.9466E−04 9.9474E−04 5.1919E−03 2.3492E−03 3.9373E−03A8 = −5.1723E−05 −9.3468E−04 −1.1693E−03 −1.5213E−03 −5.3706E−04−2.4237E−03 A10 = −9.3109E−05 2.8813E−04 2.3067E−04 2.5475E−041.2246E−04 8.8342E−04 A12 = −5.5615E−05 −1.1608E−05 −1.6807E−05−2.6469E−05 −1.4672E−04 A14 = −7.0094E−08 4.1745E−08 2.3106E−061.0202E−05 A16 = −1.8451E−07 Surface # 8 9 10 11 12 13 k = −2.0733E+00−2.2958E+00 −6.1206E+00 1.2291E+01 −2.0220E+01 −5.2096E+00 A4 =2.3077E−02 1.0940E−02 1.8437E−03 8.0291E−03 −2.1366E−02 −1.0980E−02 A6 =−1.4813E−02 −6.8922E−03 −2.1785E−04 −6.8196E−04 2.6962E−03 1.1514E−03 A8= 4.5175E−03 1.9778E−03 −2.2497E−05 −1.1978E−04 −3.0482E−04 −1.1031E−04A10 = −5.0028E−04 −2.6077E−04 −4.8977E−06 2.2827E−05 2.6749E−057.8905E−06 A12 = −9.0514E−06 1.4132E−05 1.2671E−06 −1.6251E−06−1.3971E−06 −3.5786E−07 A14 = 5.9248E−06 1.4372E−07 −9.6963E−085.5454E−08 3.8516E−08 8.8143E−09 A16 = −3.3050E−07 −3.0482E−082.5336E−09 −7.5502E−10 −4.3899E−10 −8.8538E−11

In the imaging lens system according to the 5th embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 5th embodiment. Moreover, these parameters can be calculated fromTable 9 and Table 10 as the following values and satisfy the followingrelationships:

5th Embodiment f [mm] 6.82 T56/CT6 1.44 Fno 2.40 |R9/R10| 0.18 HFOV[deg.] 41.5 (R11 + R12)/(R11 − R12) 2.15 (V2 + V4)/V6 0.63 f3/f1 0.56T12/CT1 1.07 f × tan(HFOV) [mm] 6.03 T12/CT2 1.53

6th Embodiment

FIG. 11 is a schematic view of an imaging lens system according to the6th embodiment of the present disclosure. FIG. 12 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 6th embodiment. In FIG. 11, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 600, a first lens element 610, a second lens element 620,a third lens element 630, a fourth lens element 640, a fifth lenselement 650, a sixth lens element 660, an IR-cut filter 680, an imageplane 670 and an image sensor 690, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 610 with positive refractive power has a convexobject-side surface 611 and a concave image-side surface 612. The firstlens element 610 is made of plastic material, and has the object-sidesurface 611 and the image-side surface 612 being both aspheric.

The second lens element 620 with negative refractive power has a convexobject-side surface 621 and a concave image-side surface 622. The secondlens element 620 is made of plastic material, and has the object-sidesurface 621 and the image-side surface 622 being both aspheric.

The third lens element 630 with positive refractive power has a convexobject-side surface 631 and a convex image-side surface 632. The thirdlens element 630 is made of plastic material, and has the object-sidesurface 631 and the image-side surface 632 being both aspheric.

The fourth lens element 640 with negative refractive power has a concaveobject-side surface 641 and a convex image-side surface 642. The fourthlens element 640 is made of plastic material, and has the object-sidesurface 641 and the image-side surface 642 being both aspheric.

The fifth lens element 650 with positive refractive power has a convexobject-side surface 651 in a paraxial region thereof and a concaveimage-side surface 652, wherein the object-side surface 651 of the fifthlens element 650 has a concave shape in an off-axis region thereof. Thefifth lens element 650 is made of plastic material, and has theobject-side surface 651 and the image-side surface 652 being bothaspheric.

The sixth lens element 660 with negative refractive power has a convexobject-side surface 661 and a concave image-side surface 662 in aparaxial region thereof, wherein the image-side surface 662 of the sixthlens element 660 has a convex shape in an off-axis region thereof. Thesixth lens element 660 is made of plastic material, and has theobject-side surface 661 and the image-side surface 662 being bothaspheric.

The IR-cut filter 680 is made of glass material and located between thesixth lens element 660 and the image plane 670, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 6th embodiment are shown in Table 11and the aspheric surface data are shown in Table 12 below.

TABLE 11 6th Embodiment f = 7.53 mm, Fno = 2.40, HFOV = 41.6 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Ape. Stop Plano −0.225 2 Lens 1 5.000 ASP0.730 Plastic 1.544 55.9 13.47 3 14.925 ASP 0.919 4 Lens 2 7.102 ASP0.600 Plastic 1.640 23.3 −21.34 5 4.518 ASP 0.333 6 Lens 3 11.660 ASP1.557 Plastic 1.544 55.9 7.31 7 −5.757 ASP 0.766 8 Lens 4 −1.608 ASP0.750 Plastic 1.640 23.3 −8.72 9 −2.669 ASP 0.080 10 Lens 5 3.495 ASP1.519 Plastic 1.544 55.9 7.67 11 18.233 ASP 1.085 12 Lens 6 4.561 ASP0.900 Plastic 1.544 55.9 −10.94 13 2.403 ASP 1.000 14 IR-cut Plano 0.300Glass 1.517 64.2 — filter 15 Plano 0.633 16 Image Plano — Note:Reference wavelength is 587.6 nm (d-line).

TABLE 12 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −1.1011E+00−1.0000E+00 −1.6386E+01 −7.4577E−01 −1.0000E+00 1.0540E+00 A4 =−1.1844E−03 −5.8548E−03 −9.1285E−03 −1.4728E−02 −7.3964E−03 −8.1218E−03A6 = −4.7390E−04 −3.4455E−04 4.7015E−04 2.4901E−03 1.0932E−03 2.6885E−03A8 = 2.1442E−06 −3.5183E−04 −4.4111E−04 −5.6013E−04 −1.9784E−04−1.1206E−03 A10 = −4.5044E−05 8.5207E−05 5.9088E−05 6.9860E−053.3745E−05 2.5538E−04 A12 = −1.6564E−05 −2.0942E−06 −3.4055E−06−5.3806E−06 −2.4733E−05 A14 = 7.0644E−08 9.3433E−09 3.6227E−076.3706E−07 A16 = 2.1903E−08 Surface # 8 9 10 11 12 13 k = −2.0483E+00−2.2454E+00 −6.0498E+00 1.0654E+01 −1.0594E+01 −4.1434E+00 A4 =7.7434E−03 3.8246E−03 3.5059E−03 9.8284E−03 −1.2724E−02 −8.9671E−03 A6 =−7.7622E−04 −9.9497E−04 −6.5287E−04 −1.3123E−03 8.7724E−04 7.6012E−04 A8= −9.5895E−04 −3.2943E−05 4.9497E−05 6.3453E−05 −5.0908E−05 −5.5152E−05A10 = 4.3061E−04 5.5323E−05 −5.2134E−06 −7.8384E−07 3.1706E−062.9652E−06 A12 = −6.9569E−05 −8.6271E−06 4.2612E−07 −5.5103E−08−1.3114E−07 −1.0247E−07 A14 = 5.1061E−06 5.6529E−07 −1.9142E−082.4477E−09 2.8268E−09 1.9516E−09 A16 = −1.4461E−07 −1.4042E−083.4434E−10 −3.1352E−11 −2.4596E−11 −1.5279E−11

In the imaging lens system according to the 6th embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 6th embodiment. Moreover, these parameters can be calculated fromTable 11 and Table 12 as the following values and satisfy the followingrelationships:

6th Embodiment f [mm] 7.53 T56/CT6 1.21 Fno 2.40 |R9/R10| 0.19 HFOV[deg.] 41.6 (R11 + R12)/(R11 − R12) 3.23 (V2 + V4)/V6 0.83 f3/f1 0.54T12/CT1 1.26 f × tan(HFOV) [mm] 6.69 T12/CT2 1.53

7th Embodiment

FIG. 13 is a schematic view of an imaging lens system according to the7th embodiment of the present disclosure. FIG. 14 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 7th embodiment. In FIG. 13, theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, anaperture stop 700, a first lens element 710, a second lens element 720,a third lens element 730, a fourth lens element 740, a fifth lenselement 750, a sixth lens element 760, an IR-cut filter 780, an imageplane 770 and an image sensor 790, wherein the imaging lens system has atotal of six lens elements with refractive power.

The first lens element 710 with positive refractive power has a convexobject-side surface 711 and a convex image-side surface 712. The firstlens element 710 is made of plastic material, and has the object-sidesurface 711 and the image-side surface 712 being both aspheric.

The second lens element 720 with negative refractive power has a convexobject-side surface 721 and a concave image-side surface 722. The secondlens element 720 is made of plastic material, and has the object-sidesurface 721 and the image-side surface 722 being both aspheric.

The third lens element 730 with positive refractive power has a concaveobject-side surface 731 and a convex image-side surface 732. The thirdlens element 730 is made of plastic material, and has the object-sidesurface 731 and the image-side surface 732 being both aspheric.

The fourth lens element 740 with negative refractive power has a concaveobject-side surface 741 and a convex image-side surface 742. The fourthlens element 740 is made of plastic material, and has the object-sidesurface 741 and the image-side surface 742 being both aspheric.

The fifth lens element 750 with positive refractive power has a convexobject-side surface 751 in a paraxial region thereof and a conveximage-side surface 752, wherein the object-side surface 751 of the fifthlens element 750 has a concave shape in an off-axis region thereof. Thefifth lens element 750 is made of plastic material, and has theobject-side surface 751 and the image-side surface 752 being bothaspheric.

The sixth lens element 760 with negative refractive power has a convexobject-side surface 761 and a concave image-side surface 762 in aparaxial region thereof, wherein the image-side surface 762 of the sixthlens element 760 has a convex shape in an off-axis region thereof. Thesixth lens element 760 is made of plastic material, and has theobject-side surface 761 and the image-side surface 762 being bothaspheric.

The IR-cut filter 780 is made of glass material and located between thesixth lens element 760 and the image plane 770, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 7th embodiment are shown in Table 13and the aspheric surface data are shown in Table 14 below.

TABLE 13 7th Embodiment f = 7.76 mm, Fno = 2.40, HFOV = 39.6 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # Length 0Object Plano Infinity 1 Ape. Stop Plano −0.175 2 Lens 1 6.090 ASP 0.766Plastic 1.544 55.9 10.59 3 −101.613 ASP 0.700 4 Lens 2 8.311 ASP 0.400Plastic 1.650 21.5 −20.20 5 4.995 ASP 0.630 6 Lens 3 −98.799 ASP 1.664Plastic 1.544 55.9 9.98 7 −5.180 ASP 1.263 8 Lens 4 −1.470 ASP 0.400Plastic 1.650 21.5 −11.94 9 −2.008 ASP 0.100 10 Lens 5 4.649 ASP 2.582Plastic 1.544 55.9 7.38 11 −23.659 ASP 0.735 12 Lens 6 3.204 ASP 0.444Plastic 1.544 55.9 −7.79 13 1.735 ASP 1.000 14 IR-cut Plano 0.300 Glass1.517 64.2 — filter 15 Plano 0.515 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 14 Aspheric Coefficients Surface # 2 3 4 5 6 7 k = −5.3596E−01−1.0000E+00 −3.6055E+01 −1.9700E+00 −3.1673E−01 9.2384E−01 A4 =−6.9829E−04 −3.1759E−03 −9.5786E−03 −1.5755E−02 −7.1568E−03 −9.1590E−03A6 = −5.3430E−04 −6.2828E−05 5.9300E−04 2.4673E−03 1.0907E−03 2.7943E−03A8 = 7.9189E−05 −3.5579E−04 −3.6992E−04 −5.4439E−04 −8.4660E−04−1.1661E−03 A10 = −4.9023E−05 8.8959E−05 6.4144E−05 6.8174E−053.2532E−04 2.9128E−04 A12 = −1.6539E−05 −4.3941E−06 −3.2960E−06−6.8228E−05 −3.7393E−05 A14 = −1.1422E−07 3.6310E−08 7.0601E−062.2011E−06 A16 = −2.7399E−07 −4.4999E−08 Surface # 8 9 10 11 12 13 k =−2.0301E+00 −2.5993E+00 −6.3564E+00 1.5494E+01 −2.6283E+01 −6.1770E+00A4 = 5.9623E−03 2.0097E−03 −5.4930E−03 6.5038E−03 −1.9807E−02−6.7207E−03 A6 = −1.4620E−03 −9.6669E−04 8.8904E−04 −5.6517E−042.8861E−03 6.0282E−04 A8 = −1.3003E−04 1.0146E−04 −1.3794E−04 2.5039E−06−3.1197E−04 −4.7491E−05 A10 = 1.9644E−04 4.1759E−05 1.1746E−051.3852E−06 2.0513E−05 2.5209E−06 A12 = −3.8976E−05 −8.7916E−06−5.3228E−07 −5.2265E−08 −7.4159E−07 −7.9865E−08 A14 = 3.0606E−065.9707E−07 9.2069E−09 5.7110E−10 1.3729E−08 1.3642E−09 A16 = −8.6196E−08−1.3193E−08 1.1654E−11 −1.0248E−10 −9.6728E−12

In the imaging lens system according to the 7th embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 7th embodiment. Moreover, these parameters can be calculated fromTable 13 and Table 14 as the following values and satisfy the followingrelationships:

7th Embodiment f [mm] 7.76 T56/CT6 1.66 Fno 2.40 |R9/R10| 0.20 HFOV[deg.] 39.6 (R11 + R12)/(R11 − R12) 3.36 (V2 + V4)/V6 0.77 f3/f1 0.94T12/CT1 0.91 f × tan(HFOV) [mm] 6.42 T12/CT2 1.75

8th Embodiment

FIG. 15 is a schematic view of an imaging lens system according to the8th embodiment of the present disclosure. FIG. 16 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimaging lens system according to the 8th embodiment. In FIG. 15 theimaging lens system includes six non-cemented lens elements withrefractive power, in order from an object side to an image side, a firstlens element 810, an aperture stop 800, a second lens element 820, athird lens element 830, a fourth lens element 840, a fifth lens element850, a sixth lens element 860, an IR-cut filter 880, an image plane 870and an image sensor 890, wherein the imaging lens system has a total ofsix lens elements with refractive power.

The first lens element 810 with positive refractive power has a convexobject-side surface 811 and a concave image-side surface 812. The firstlens element 810 is made of glass material, and has the object-sidesurface 811 and the image-side surface 812 being both aspheric.

The second lens element 820 with negative refractive power has a convexobject-side surface 821 and a concave image-side surface 822. The secondlens element 820 is made of plastic material, and has the object-sidesurface 821 and the image-side surface 822 being both aspheric.

The third lens element 830 with positive refractive power has a convexobject-side surface 831 and a convex image-side surface 832. The thirdlens element 830 is made of plastic material, and has the object-sidesurface 831 and the image-side surface 832 being both aspheric.

The fourth lens element 840 with negative refractive power has a concaveobject-side surface 841 and a convex image-side surface 842. The fourthlens element 840 is made of plastic material, and has the object-sidesurface 841 and the image-side surface 842 being both aspheric.

The fifth lens element 850 with positive refractive power has a convexobject-side surface 851 in a paraxial region thereof and a planarimage-side surface 852, wherein the object-side surface 851 of the fifthlens element 850 has a concave shape in an off-axis region thereof. Thefifth lens element 850 is made of plastic material, and has theobject-side surface 851 and the image-side surface 852 being bothaspheric.

The sixth lens element 860 with negative efractive power has a concaveobject-side surface 861 and a concave image-side surface 862 in aparaxial region thereof, wherein the image-side surface 862 of the sixthlens element 860 has a convex shape in an off-axis region thereof. Thesixth lens element 860 is made of plastic material, and has theobject-side surface 861 and the image-side surface 862 being bothaspheric.

The IR-cut filter 880 is made of glass material and located between thesixth lens element 860 and the image plane 870, and will not affect thefocal length of the imaging lens system.

The detailed optical data of the 8th embodiment are shown in Table 15and the aspheric surface data are shown in Table 16 below.

TABLE 15 8th Embodiment f = 9.41 mm, Fno = 2.80, HFOV = 39.9 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 5.646 ASP 1.529 Glass 1.587 59.5 12.192 24.048 ASP 0.059 3 Ape. Stop Plano 0.857 4 Lens 2 10.778 ASP 0.400Plastic 1.640 23.3 −21.92 5 6.006 ASP 0.343 6 Lens 3 18.735 ASP 1.866Plastic 1.535 55.7 8.62 7 −5.903 ASP 0.656 8 Lens 4 −1.693 ASP 0.790Plastic 1.640 23.3 −10.79 9 −2.652 ASP 0.156 10 Lens 5 4.603 ASP 1.578Plastic 1.535 55.7 8.60 11 ∞ ASP 0.892 12 Lens 6 −13.870 ASP 2.374Plastic 1.544 55.9 −9.07 13 8.120 ASP 0.800 14 IR-cut Plano 0.300 Glass1.517 64.2 — filter 15 Plano 0.900 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 16 Aspheric Coefficients Surface # 1 2 4 5 6 7 k = −3.2504E−01−4.1514E+01 −4.2050E+01 1.8936E+00 4.9145E+00 1.0595E+00 A4 = 6.8875E−06−1.2393E−03 −6.6525E−03 −1.1454E−02 −3.1021E−03 −1.7683E−03 A6 =−1.6378E−05 9.7646E−05 4.4418E−04 1.3832E−03 1.4160E−04 4.7616E−05 A8 =−4.8234E−06 −2.3094E−04 −1.7586E−04 −2.5432E−04 −2.0643E−05 −8.0984E−05A10 = −1.4269E−06 8.1444E−05 3.1130E−05 3.6251E−05 −2.8915E−061.9314E−05 A12 = −1.1517E−05 −4.0952E−06 −3.1142E−06 6.4568E−07−1.9290E−06 A14 = 1.3872E−07 1.1253E−07 −2.0380E−08 7.0945E−08 Surface #8 9 10 11 12 13 k = −2.7430E+00 −3.2440E+00 −1.0568E+01 0.0000E+002.7389E+00 −1.8093E−01 A4 = −5.5142E−03 −3.2984E−03 −3.4041E−03−1.9452E−03 −3.3709E−03 −2.9508E−03 A6 = 1.7432E−04 −3.9394E−058.5820E−04 3.8637E−04 −1.2791E−04 1.5950E−05 A8 = 1.3124E−05 1.2973E−05−1.5643E−04 −1.8730E−05 3.8014E−05 2.4193E−06 A10 = 3.6809E−063.3667E−07 1.6028E−05 −2.0185E−06 −2.1446E−06 −1.0574E−07 A12 =−2.4174E−08 1.3619E−08 −1.1521E−06 2.0925E−07 5.7844E−08 1.9207E−09 A14= −1.2473E−08 3.6148E−10 4.6596E−08 −6.5682E−09 −7.7820E−10 −1.7491E−11A16 = −7.4977E−10 7.0195E−11 3.9913E−12 6.0921E−14

In the imaging lens system according to the 8th embodiment, thedefinitions of these parameters shown in the following table are thesame as those stated in the 1st embodiment with corresponding values forthe 8th embodiment. Moreover, these parameters can be calculated fromTable 15 and Table 16 as the following values and satisfy the followingrelationships:

8th Embodiment f [mm] 9.41 T56/CT6 0.38 Fno 2.80 |R9/R10| 0.00 HFOV[deg.] 39.9 (R11 + R12)/(R11 − R12) 0.26 (V2 + V4)/V6 0.83 f3/f1 0.71T12/CT1 0.60 f × tan(HFOV) [mm] 7.87 T12/CT2 2.29

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. It is to be noted thatTABLES 1-16 show different data of the different embodiments; however,the data of the different embodiments are obtained from experiments. Theembodiments were chosen and described in order to best explain theprinciples of the invention and its practical applications, to therebyenable others skilled in the art to best utilize the invention andvarious embodiments with various modifications as are suited to theparticular use contemplated. The embodiments depicted above and theappended drawings are exemplary and are not intended to be exhaustive orto limit the scope of the present disclosure or invention to the preciseforms disclosed. Many modifications and variations are possible in viewof the above teachings.

What is claimed is:
 1. An imaging lens system comprising sixnon-cemented lens elements with refractive power, in order from anobject side to an image side: a first lens element having positiverefractive power; a second lens element having refractive power; a thirdlens element having positive refractive power, a fourth lens elementhaving refractive power; a fifth lens element having refractive power,wherein both of an object-side surface and an image-side surface of thefifth lens element are aspheric; and a sixth lens element withrefractive power having a concave image-side surface in a paraxialregion thereof, wherein the image-side surface of the sixth lens elementhaving at least one convex shape in an off-axis region thereof, and bothof an object-side surface and the image-side surface of the sixth lenselement are aspheric; wherein the imaging lens system has a total of sixlens elements with refractive power, a focal length of the first lenselement is f1, a focal length of the third lens element is f3, acurvature radius of the object-side surface of the fifth lens element isR9, a curvature radius of the image-side surface of the fifth lenselement is R10, a central thickness of the first lens element is CT1,and an axial distance between the first lens element and the second lenselement is T12, the following relationships are satisfied:0<f3/f1<1.1;|R9/R10|<3.0; and0.90<T12/CT1<3.0.
 2. The imaging lens system of claim 1, wherein thefirst lens element has a convex object-side surface and the third lenselement has a convex image-side surface.
 3. The imaging lens system ofclaim 2, wherein the fifth lens element has positive refractive powerand the sixth lens element has negative refractive power.
 4. The imaginglens system of claim 3, wherein the fourth lens element has negativerefractive power.
 5. The imaging lens system of claim 3, wherein thefourth lens element has a concave object-side surface and a conveximage-side surface.
 6. The imaging lens system of claim 3, wherein thefocal length of the first lens element is f1, the focal length of thethird lens element is f3, and the following relationship is satisfied:0.20<f3/f1<0.85.
 7. The imaging lens system of claim 3, wherein acentral thickness of the second lens element is CT2, the axial distancebetween the first lens element and the second lens element is T12, andthe following relationship is satisfied:1.20<T12/CT2<30.
 8. The imaging lens system of claim 3, wherein thecurvature radius of the object-side surface of the fifth lens element isR9, the curvature radius of the image-side surface of the fifth lenselement is R10, and the following relationship is satisfied:|R9/R10|<1.0.
 9. The imaging lens system of claim 3, wherein an Abbenumber of the second tens element is V2, an Abbe number of the fourthlens element is V4, an Abbe number of the sixth lens element is V6, andthe following relationship is to satisfied:0.60<(V2+V4)/V6<1.10.
 10. The imaging lens system of claim 3, wherein acurvature radius of the object-side surface of the sixth lens element isR11, a curvature radius of the image-side surface of the sixth lenselement is R12, and the following relationship is satisfied:−1.0<(R11+R12)/(R11−R12)<2.75.
 11. The imaging lens system of claim 1,wherein the object-side surface of the fifth lens element is convex in aparaxial region thereof, wherein the object-side surface of the fifthlens element has at least one concave shape in an off-axis regionthereof.
 12. The imaging lens system of claim 1, further comprising: astop located between an imaged object and the second lens element; andat least three lens elements among the first through sixth lens elementsare made of plastic material.
 13. The imaging lens system of claim 1,further comprising: an image sensor, wherein the image sensor has aresolution of at least 10 megapixels.
 14. An imaging lens systemcomprising six non-cemented lens elements with refractive power, inorder from an object side to an image side: a first lens element havingpositive refractive power; a second lens element having negativerefractive power; a third lens element having positive refractive power;a fourth lens element with refractive power having a concave object-sidesurface and a convex image-side surface; a fifth lens element withrefractive power having a convex object-side surface, wherein both ofthe object-side surface and an image-side surface of the fifth lenselement are aspheric; and a sixth lens element with refractive powerhaving a concave image-side surface in a paraxial region thereof,wherein the image-side surface of the sixth lens element having at leastone convex shape in an off-axis region thereof, and both of anobject-side surface and the image-side surface of the sixth lens elementare aspheric; wherein the imaging lens system has a total of six lenselements with refractive power, a focal length of the first lens elementis f1, a focal length of the third lens element is f3, a curvatureradius of the object-side surface of the fifth lens element is R9, acurvature radius of the image-side surface of the fifth lens element isR10, a curvature radius of the object-side surface of the sixth lenselement is R11, a curvature radius of the image-side surface of thesixth lens element is R12, and the following relationships aresatisfied:0<f3/f1<1.1;|R9/R10|<3.0; and−1.0<(R11+R12)/(R11−R12)<2.75.
 15. The imaging lens system of claim 14,wherein the first lens element has a convex object-side surface and thethird lens element has a convex image-side surface.
 16. The imaging lenssystem of claim 15, wherein the fifth lens element has positiverefractive power and the sixth lens element has negative refractivepower.
 17. The imaging lens system of claim 15, wherein the fourth lenselement has negative refractive power.
 18. The imaging lens system ofclaim 15, wherein the curvature radius of the object-side surface of thesixth lens element is R11, the curvature radius of the image-sidesurface of the sixth lens element is R12, and the following relationshipis satisfied:−0.50<(R11+R12)/(R11−R12)<2.50.
 19. The imaging lens system of claim 15,wherein the second lens element has a convex object-side surface and aconcave image-side surface.
 20. The imaging lens system of claim 15,wherein a central thickness of the second lens element is CT2, an axialdistance between the first lens element and the second lens element isT12, and the following relationship is satisfied:1.20<T12/CT2<3.0.
 21. The imaging lens system of claim 15, wherein thefocal length of the first lens element is f1, the focal length of thethird lens element is f3, and the following relationship is satisfied:0.20<f3/f1<085.
 22. The imaging lens system of claim 15, wherein anaxial distance between the fifth lens element and the sixth lens elementis T56, a central thickness of the sixth lens element is CT6, and thefollowing relationship is satisfied:0.8<T56/CT6<2.5.
 23. The imaging lens system of claim 15, wherein atleast three lens elements among the first through sixth lens elementsare made of plastic material, a focal length of the imaging lens systemis f, a half of a maximal field of view of the imaging lens system isHFOV, and the following relationship is satisfied:5.5 mm<f×tan(HFOV)<10 mm.
 24. An image capturing device, comprising theimaging lens system as set forth herein in claim 14 and an image sensorlocated on an image plane side of said imaging lens system.